1. Field of the Invention
Example embodiments of the present invention relate to a method of forming a photosensitive pattern, a method of manufacturing a display substrate, and a display substrate. More particularly, example embodiments of the present invention relate to a method of forming a photosensitive pattern using a digital exposure device (which includes micro-mirrors), a method of manufacturing a display substrate using the digital exposure device, and a display substrate.
2. Description of the Related Art
Generally, a thin-film transistor (“TFT”) and signal lines electrically connected to the TFT are formed by a photolithography process. The photolithography process includes an exposure step, a developing step, and an etching step. In the exposure step, a photoresist pattern is formed using a mask, which is associated with a design of a metal pattern, and an exposure device. Whenever the design of the metal pattern is changed, a design of the mask needs to be changed; therefore, the number of the masks depends on the number of the metal patterns. Since the cost of manufacturing the mask is significantly high, the mask used for the photolithography process substantially increases the manufacturing cost of display substrates, and therefore substantially increases the production cost of display devices.
Recently, in order to solve the above-mentioned problem, a digital exposure device using an optical element including a plurality of micro-mirrors capable of providing a plurality of spot beams onto a substrate without using an additional mask has been used. In the digital exposure device, the micro-mirrors are individually turned on or off, and the spot beams respectively corresponding to the micro-mirrors turned on are provided to the substrate, so that a specific area of the substrate is selectively exposed. Thus, a shape of a photoresist pattern may be determined by an operation time of turning on/off the micro-mirrors and an irradiated position of the spot-beams.
Typically, the digital exposure device theoretically calculates the irradiated position of the spot beams prior to turning on or off the micro-mirrors, and the theoretically calculated irradiated position and the actual irradiated position of the spot beams are usually different from each other. Because of the difference between the theoretically calculated irradiated position and the actual irradiated position, a predetermined position preset by an operator may not receive a light with sufficient light intensity, and thus a photoresist pattern formed using the digital exposure device has portions in which the light is not desirably provided. As a result, the reliability of the photoresist pattern and the pattern formed using the photoresist pattern may be undesirable.